Getting a phone number
Your orchestra needs a phone number. People might want to call for information about upcoming concerts, and you might need to enter a phone number for various bureaucratic forms you're filling out. I recommend against using your own phone number or the number of any of your members. Members and leadership change, but you want your organization's contact information to remain stable over time.
Google Voice is an excellent option for securing a dedicated phone number for your organization at no charge. Google Voice allocates you a phone number without actually giving you phone service. Calls made to that number are redirected to the number(s) you designate in the Google Voice settings. So, if someone calls your orchestra's phone number, and you've configured Google Voice to forward calls to your personal cell number, then your cell phone will ring, and you can take the call. If your designated phone answerer steps down from the job, you can just set Google Voice to redirect calls to your new designated phone answerer, and the orchestra's number doesn't change. It also gives you voicemail and text services, and it can send e-mail messages indicating when a new voicemail or text message has been received, so you don't have to remember to log in and check. The best part is that it's free.
Google Voice can be part of your orchestra's Google account, which gives you access to a bunch of other useful tools. You just have to activate the Google Voice portion and set it up.